1. Field of the Invention
The present invention is directed to cylinder head gaskets for establishing a fluid-tight seal between an engine block and a cylinder head of a piston driven internal combustion engine.
2. Related Art
In a continuing effort to improve fuel economy while improving or at least maintaining power output, engine manufacturers have increasingly been employing advanced technologies, such as direct injection, turbochargers and superchargers. One common effect of these advanced technologies is increased combustion pressures and temperatures. During operation of the engine, this may result in increased movement of the cylinder head relative to the engine block as the combustion of a fuel and air mixture within a plurality of cylinder bores tends to energize the cylinder head away from the engine block. It is important for the cylinder head gasket to maintain a fluid tight seal during the lifting movement of the cylinder head away from the engine block in order to trap the combustion gasses in the combustion bore.
Some cylinder head gaskets include multiple layers, at least one of which has an embossed bead formed therein for resiliently flexing to maintain the fluid-tight seals with the engine block and cylinder head.